The 2018 Codebreaker Challenge consists of a series of tasks that are worth a varying amount of points based
upon their difficulty. In previous years, tasks had to be solved in order to unlock the next task and
rankings were based upon the quantity of solvers that progressed the furthest from each school. This
way of ranking heavily weighted progression above participation and did not allow for skipping ahead
if a particular task became a stumbling block. So to address these issues, ALL tasks will be available
immediately upon registration and can be solved in any order. The point value associated with each task is based on
relative difficulty and schools will be ranked according to total number of points accumulated by their students.
It is still recommended to solve tasks in order since the tasks flow with the storyline, but that is no longer a
requirement.

Background

DISCLAIMER - The following is a FICTITIOUS story meant for providing realistic context for the Codebreaker Challenge and
is not tied in any way to actual events.

A new strain of ransomware has managed to penetrate several critical
government networks and NSA has been called upon to assist in
remediating the infection to prevent massive data losses. For each
infected machine, an encrypted copy of the key needed to decrypt the ransomed
files has been stored in a smart contract on the Ethereum blockchain*
and is set to only be unlocked upon receipt of the ransom payment. Your
mission is to ultimately (1) find a way to unlock the ransomware
without giving in to the attacker’s demands and (2) figure out a way to
recover all of the funds already paid by other victims. Are YOU up to
the challenge?

* - for the purposes of this challenge, a private blockchain has been
created with no real monetary value associated with the Ether. See http://www.ethdocs.org/en/latest/ for
more information about Ethereum.

The Codebreaker Challenge was developed by the National Security Agency. Check us out at nsa.gov.